Screening apparatus.



PATENTEDHJUNE 9, 1908. E. HVNUTTER.

SCREENING APPARATUS. APPLICATION 11.31) my 11, 1907.

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ATTORNEYS TH: NORRIS PETER: 270., umsulmrrcu, n. c.

" No. 890,527. I PATENTED JUNE 9,- 1908..

E NUTTER.

SCREENING APPARATUS.

APPLIUATION FILED MAY 11, 1907.

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WITNESSES INVENTOH W I A THE Nam-us PETERS :mfumsumnmu. D. c

EDWARD HOIT NUTTER, OF TELLURIDE, COLORADO.

SCREEN IN G APPARATUS.

Specification of Letters Patent.

Patented June 9, 1908.

Application filed May 11, 1907. Serial No. 373,024..

To all whom it may concern:

Be it known that I, EDWARD H. NUTTER, a citizen of the United States,and a resident of Telluride, in the county of San Miguel and State ofColorado, have invented a new and Improved Screening Apparatus, of whichthe following is a full, clear, and exact description.

This invention relates to screening apparatus, and it is particularlyuseful in connection with devices of this class used for the purpose ofscreening and separating crushed ores, broken stone, ground cement, andsimi lar substances into grades of varying degrees of coarseness.

The object of the invention is to provide a simple, strong and efficientscreenmg apparatus for separating crushed material, such as ores, stoneand the like, into different grades, and for removing foreign substancesfrom the crushed material.

A further object of the invention is to provide an apparatus of theclass described, hav

ing a movable or a rigid screen and provided with means for forcingimpulsive air currents or currents of other gases than air against saidscreen.

The invention consists in the construction and combination of parts tobe more articularly described hereinafter and ful y set forth in theclaims.

Reference is to be had to the accompanying drawings forming a part ofthis specification, in which,

Figure 1 is a vertical cross-section through a screening apparatus withmy invention applied thereto Fig. 2 is a vertical cross-section ofanother form of the a paratus; and Fig. 3 is a similar view of stillanother form of my invention.

Like characters of reference designate cor responding parts in all theviews.

Before proceeding to a more detailed explanation of the invention itshould be understood that for the purpose of separating crushed ores andthe like into varying grades corresponding to the degree of division,screens of wire or other suitable material are employed, which may beagitated to pass material of certain size therethrough, and againstwhich currents of air may be forced for the same purpose. The materialpassing through the screen is known as under-size, while the materialrejected by the screen is known as over-size. The arrangement is suchthat the over-size is rejected at the edge of the screen and is carriedoff by a receiving hopper or chute. To effect this purpose, the screenmay be inclined to permit the undersize to slide along the same to thereceiver, or the screen may be actuated to move the rejected material tothe edge of the screen.

the belt when the same passes over the roller arranged above theover-size receiver. I employ means for forcing air against the screen'inmy apparatus in an impulsive current, a reciprocating member directingalternate currents of air against the opposite sides ofthe screen inopposite directions. In this way the under-size is rapidly forcedthrough the meshes of the screen, which tends to loosen particles of thematerial clinging to the screen and tending to choke the same.

Referring more particularly to the drawings, Fig. 1 represents ascreening apparatus in which the screen is rotated in order to removethe over-size by means of centrifugal action. bers of the frame of thescreen, carrying transverse members 2 and uprights 3 mounted upon thetransverse members. Inclined braces 4 connect the transverse members andthe uprights 3. A cylindrical casing 5 is mounted vertically upon theframe and has arranged therein a piston 6 provided with a pivotedpiston-rod 7. The connecting rod 7 extends upwardly from the casing andhas 1 are uprights or supporting memthe end mounted at a crank 8 of atransverse shaft 9 carried by the uprights 3, in suitable bearings 10 attheir upper extremities. The shaft 9 has at one end a fly-wheel 11 andat the opposite end a sprocket 12. Underneath the transverse members 2is a second shaft 13 carried in shaft bearings 14 and provided with asprocket 15. The shaft 13 is substantially in alinement with the shaft 9and has a pulley 16 by means of which it can be suitably belted to aprime mover. It will be understood that the screening apparatus can beoperated by means of any preferable or common motive device. A chain 17operatively connects the sprockets 12 and 15 so that when the shaft 13is actuated, the shaft 19 is similarly actuated, thereby reci rocatingthe piston 6 within the cylindrical casing 5. A delivery hopper 18 isarranged at one of the uprights 3 adjacent to the cylindrical casing,and has a delivery spout 19 extending shaft 13 is actuated the shaft 20is rotated within the casing. At its upper end the shaft 20 is providedwith a head 23 upon which is mounted a circular screen 24 adapted torotate within the cylindrical casing. Arranged at the side of the casingis an oversize receiver 24'" having an opening adapted to receive theover-size material thrown to the edge of the rotating screen bycentrifugal action. A11 inclined annular flange 25 is mounted on theinner wall of the casing to receive material from the edge of the screenand direct the same to the receiver 24. Arranged underneath the screenand extending through the opening 26 in the wall of the easing is achute 27 constituting an under-size receiver to receive the materialpassing through the meshes of the screen.

The'operation of the screening apparatus is as follows: The material tobe separated or screened is thrown into the delivery hopper and passesdown the delivery spout 19 upon the screen, the latter revolvingrapidly, and under the influence of the agitation due to the revolutionand the impulsive air currents forced by the piston 6 against thescreen, the under-size material passes through the meshes of the wireand the over-size material is carried rapidly to the edges of the screenand passes into the over-size receiver and through the latter tosuitable bins. Similarly, the under-size material falls upon theunder-size receiver and passes from the same to other suitable bins.

In the modified form illustrated in Fig. 2,

' the screen is in the form of an endless belt 28 ed above the belt andhas an outwardly flaring end 32 presenting an opening adjacent to theupper run of the belt; and under the upper run of the belt and below theopening of the cylindrical casing 31is an undersize receiver 33. Theover-size material is carried away by the belt which moves in thedirection indicated by the arrow and falls into an over-size receiver 34arranged adj acent to the roller 29. A delivery hopper 35 is arrangedadjacent to the casing 31 and has a deliveryspout 36 directed towardsthe belt near the opening of the casing. ithin the casing 31 areciprocable piston 37 is provided for pulsating the air against thebelt screen. The operation of this form of the device is similar to theoperation of the form described before the air currents forcing theunder-size through the meshes of the screen into the under-sizereceiver, while at the same time the meshes of the belt are preventedfrom clogging, owing to the impulsive nature of the air current. Thebelt itself, carries away the over-size material. The reciprocablepiston '37 is operated from the screening mechanism which drives therollers 29 and 30.

' further modified form is shown in Fig. 3 and comprises a cylindricalcasing 38 having a reciprocable piston 39 which is operated in anypreferable or common manner. A delivery hopper 40 is arranged adjacentto the casing 38 and has a delivery spout 41 discharging through asuitable opening in the Wall of the casing. An inclined screen 42 isrigidly mounted within the casing. An oversize receiver 43 extends fromthe casing at an edge of the screen through a suitable opening in theside of the casing. The over-size material falling upon the screen rollsdown the same through the action of gravity and passes into theover-size receiver. An inclined under-size receiver 44 is mounted withinthe casing underneath the screen 42 and has a discharge spout 45 topermit the under-size material to pass from the casing. In this form ofmy invention the over-size is not removed from the screen mechanically,butsimply passes from the same under the influence of its gravitationalaction.

If so desired, I may employ a diaphragm in place of the piston forpulsating the air, or any other common or preferred means for thispurpose, the principle of the invention remaining the same.

Having thus described my invention, I claim as new and desire to secureby Letters Patent:

1. A device of the class described, comprising a screen, means fordelivering material to the screen, and means for directing a series ofintermittent air impulses against and through the screen from the upperside thereof.

2. A device of the class described, comprising a screen, means fordelivering material to the screen, and means for directing a series ofintermittent air impulses against and through the screen from the upperside thereof, said means comprising a cylinder at one end of which thescreen is supported, a piston in the cylinder, and means forreciprocating the piston.

3. A device of the class described, comprising a movable screen, meansfor delivering material to the screen, and means-for directing a seriesof intermittent air impulses against and through the screen from theupper side thereof, said means comprising a cylinder at one end of whichthe screen is supported, a piston in the cylinder, and means forreciprocating the piston.

4. A device of the class described, comone end thereof, means fordelivering mate- In testimony whereof I have signed my rial to thescreen, means for rotating the name to this speclficatlon 1n thepresence of screen, and means for directing a series of intwosubscribing W1tnesses.

termittent air impulses against and through EDl/VARD HOIT NUTTER. 5 thescreen from the upper side thereof, said Witnesses:

means comprising a piston in the cylinder, WILLIAM F. HURLEY,

and means for reciprocating the piston. W. ROY EGHTERNAOH.

